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Glycogen phosphorylase 2 (gp-2) is a key enzyme during the development of Dictyostelium discoideum. The gp-2 enzyme breaks down glycogen into glucose monomers that are subsequently used to synthesize the terminal end products of cellular differentiation. This gene is an ideal candidate for studying the process of selective gene expression because its product figures so prominently in the development of this organism, implying a dependable control mechanism responsible for its developmentally regulated expression. I present in this thesis the identification of several putative cis-acting elements of gp-2 as revealed through footprint analysis. Due to the extreme AT-bias characteristic of Dictyostelium promoters, footprinting conditions required intensive optimization with respect to template, nonspecific competitor, source of protein extract and DNase I digestion. Using an endlabeled fragment containing seven repeated sequences (3 TA boxes [TAATTATA], 2 TAG boxes [TAAAAATGGT] and 2 C boxes [ACCCACT]), purified replication protein A and several developmental nuclear extracts were tested for DNA binding activity. Small footprints were observed on the TAG and C boxes of the promoter for both protein sources. However, using a more sensitive footprinting strategy involving multiple rounds of primer extension, larger footprints spanning the same promoter regions were detected. In both cases, the appearance of the footprints coincided with the documented transcriptional activity of the gene. It can be concluded from the data obtained that the TAG and C boxes are very likely cis-acting elements involved in the regulation of gp-2 expression. / Master of Science

Global CO2 emissions produced by energy-related processes, mainly power plants, have increased rapidly in recent decades; and are widely accepted as the dominant contributor to the greenhouse gas (GHG) effect and consequent climate changes. Among countermeasures against the emissions, CO2 capture and storage (CCS) is receiving much attention. Capture of CO2 is the core step of CCS as it contributes around 75% of the overall cost, and may increase the production costs of electricity by over 50%. The reduction in capture costs is one of the most challenging issues in application of CCS to the energy industry. Using limestone in CaO-looping cycles is a promising capture technology to provide a cost-effective separation process to remove CO2 content from power plants operations. Limestone has the advantage of being relatively abundant and cheap, and that has already been widely used as a sorbent for sulphur capture. However, this technology suffers from a critical challenge caused by the decay in the sorbent capture capacity during cyclic carbonation/calcination, which results in the need for more sorbent make-up; hence a reduction in cost efficiency of the technology. The performance of sorbent influenced by several operating and reaction conditions. Therefore, much research involves investigation of influencing factors and different methods to reduce the sorbent deactivation. Cont/d.

Backrounds: Usage of addictive substances is a factor which affects the reproductive health of the female users, it affects their risky sexual behavior and fetus healthy development during pregnancy of drug using mothers. Pregnancy also represents a moment in their lifes which affects certain bio-psycho-social aspects forming the beginning of usage of substance abuse. Objectives: The aim of the research was to map a degree and paterns among problem female drug users and changes throughout pregnancy, map the risks of their sexual behavior and quality of their reproductive health, try to find out the availability of gynacology care for female drug users, the amount of care available before, through and after pregnancy. It also includes specific needs and factors affecting reproductive health. Methods and research group: A questionnaire survey of 25 problem female users based on consultations with them, all of them giving birth at least once, was carried out. The study took place at K-center Sananim, using a Field program Progressive, o.s. and around this facility and the place of field program using the "snow ball method". The questionnaire included 164 items in the following parts "Sociodemographic data", "Drug Use", "Risky sexual behavior and reproductive health", "Gynecologic care and barriers to...

La combustion en boucle chimique (CLC) est une nouvelle technologie prometteuse, qui implique la séparation inhérente du dioxyde de carbone (CO2) avec une perte minimale d'énergie. Un transporteur d'oxygène est utilisé pour le transfert de l'oxygène en continu du "réacteur air" vers le "réacteur fuel" où l'oxygène est apporté au combustible. Ainsi, le contact direct entre l'air et le combustible est évité. Le gaz résultant est riche en CO2 et n'est pas dilué avec de l'azote. Le transporteur d'oxygène réduit est ensuite transporté vers le "réacteur air" afin d'être ré-oxydé, formant ainsi une boucle chimique.Ce manuscrit présente des études conduites en utilisant une nouvelle configuration de CLC de 10 kWth construite pour étudier une large gamme de conditions opératoires. Cette unité met en oeuvre le concept des lits fluidisés interconnectés en utilisant des vannes-en-L pour contrôler le débit de solide et des siphons pour minimiser les fuites de gaz. L'hydrodynamique de la circulation de solide a été étudiée sur une maquette froide et un pilote chaud. Un modèle de la circulation du solide a ensuite été développé sur le principe du bilan de pression.L'hydrodynamique de la phase gaz dans le réacteur a été étudiée expérimentalement en utilisant la distribution des temps de séjour (DTS). Un modèle hydrodynamique a été développé sur le principe du lit fluidisé bouillonnant à deux phases. La combustion du méthane a été étudiée avec NiO/NiAl2O4 comme transporteur d'oxygène. De bonnes performances de combustion et de captage de CO2 ont été atteintes. Un modèle de réacteur a été finalement mis au point en utilisant le modèle hydrodynamique du lit fluidisé bouillonnant développé précédemment et en adaptant un schéma réactionnel à cette configuration / Chemical looping combustion (CLC) is a promising novel combustion technology involving inherent separation of carbon dioxide with minimum energy penalty. An oxygen carrier is used to continuously transfer oxygen from the air reactor to the fuel reactor where the oxygen is delivered to burn the fuel. Consequently, direct contact between the air and the fuel is prevented. The resulting flue gas is rich in CO2 without N2 dilution. The reduced oxygen carrier is then transported back to the air reactor for re-oxidation purposes, hence forming a chemical loop.This dissertation presents studies conducted on a novel 10 kWth CLC configuration built to investigate a wide range of conditions. The system employs concept of interconnected bubbling fluidized beds using L-valves to control solid flow rate and loop-seals to maximize gas tightness. Hydrodynamics of solid circulation was investigated with a cold flow prototype and a high temperature pilot plant in a wide temperature range. A solid circulation model was developed based on the experimental results using the pressure balance principle. Hydrodynamic of the gas phase in the reactors was investigated through RTD studies. A hydrodynamic model was then developed based on the two phase model of bubbling fluidized beds. Methane Combustion was experimentally studied in the pilot plant using NiO/NiAl2O4 oxygen carriers. Good combustion performances and CO2 capture efficiency were achieved. A reactor model was finally developed using the previously developed hydrodynamic model of bubbling fluidized bed and adapting a reaction scheme

La criminalité sexuelle constitue aujourd’hui l’un des enjeux politiques et sociaux de nos sociétés contemporaines. Les débats auxquels elle donne lieu sont généralement l’occasion de souligner le rôle central des criminels sexuels récidivistes et de certains types de personnalités particulièrement dangereuses, parfois désignés sous le terme de « prédateurs sexuels », les plus dangereux étant les tueurs en série en raison de leur violence sexuelle meurtrière et les pédophiles en raison d’une inclination qui non seulement repousserait les limites de la morale en les amenant à s’en prendre à des enfants mais qui, de plus, pourrait participer, selon les théoriciens de l’abuseur-abusé, à reproduire un contingent d’agresseurs sexuels toujours plus important. Dans un tel contexte cette recherche doctorale a tout d’abord eu pour objectifs de contribuer à une meilleure connaissance des catégories de tueur en série et de pédophile ; d’analyser ensuite comment un ensemble de pratiques et d'idées à-travers un processus de catégorisation sont amenées à être pensées comme relevant d'un problème plus large, en l’occurrence la criminalité sexuelle ; et, enfin, inspiré par l’approche de Ian Hacking des maladies mentales transitoires de mettre en évidence les effets de la catégorisation sur les individus ainsi catégorisés et l’action en retour de ces derniers sur les catégories. / Sex-related crime is currently one of the most concerning political and social issues of our day. The resulting debates usually highlight the central role of repeat sex offenders and a number of particularly dangerous types of personality, often referred to as “sexual predators”, the most dangerous of which are serial killers, who are responsible for sexual violence and death, and paedophiles. The latter display an inclination that far exceeds moral boundaries by targeting children as victims, and could also, according to the theorists of the abuser-abused relationship, reproduce a more significant contingent of sexual aggressors. Within this context, this doctoral research aims first to contribute towards a better understanding of serial killer and paedophile categories and, subsequently analyse how, through a long categorisation process, specific practices and ideas are considered relevant to the broader issues regarding sexual criminality. Finally, this research, inspired by Ian Hacking’s approach to transitory mental illness, seeks to underline the effects that categorisation has on the persons concerned, including the latter’s influence on the former.

Les travaux menés dans cette Thèse ont consisté à développer un pilote expérimental prouvant la faisabilité de la capture de CO2 par boucle chimique calcium en utilisant des chaudières du type Lit Fluidisé Circulant. Ceux-ci ont été conduits en deux phases: une phase expérimentale à l'échelle du laboratoire avec l'interprétation théorique des résultats et une phase expérimentale à l'échelle du pilote dans le but de valider le procédé. Les résultats expérimentaux à 1'échelle du laboratoire ont permis de montrer que le frittage de CaOest la cause de la décroissance du taux de carbonatation au cours des cycles successifs calcination/carbonatation. La vitesse de frittage étant accélérée par la présence de CO2 pendant la phase de calcination. Les analyses menées sur les échantillons calcinés ont révélé l'apparition d'une structure de micrograin à l'intérieur des grains initiaux de carbonate. Les micrograins de CaO non frittés sont le siège de la réaction de carbonatation.Un procédé de capture de CO2 par boucle chimique calcium a été conçu et réalisé. Il se compose de deux lits fluidisés circulants, un réacteur de carbonatation assurant la capture du CO2 et un réacteur de calcination permettant la régénération de la chaux. Ces deux lits fluidisés circulants sont couplés de façon à permettre un fonctionnement continu du procédé de capture de CO2. Malgré le faible rendement de capture obtenu à l'échelle de ce pilote (entre 18 à 23%), ces résultats apparaissent encourageants pour le développement de cette technologie, compte tenu du fait que beaucoup de facteurs limitant le rendement de capture disparaissent avec le changement d'échelle. / The works led in this Thesis consisted in developing an experimental pilot proving CO2 capture feasibility by calcium chemical looping using Circulating Fluidised Bed as boilers. These were undertaken in two step: At the laboratory scale with theoretical interpretation of the experimental results and at the pilot scale in the aim to validate the process.The experimental results on the scale of the laboratory allowed to show that the sintering of CaO bring about the decreasing of the carbonation rate during calcination/carbonation cycles. The sintering velocity are accelerated by CO2 during the calcinations step. The analysis of the calcined samples showed a micrograins structure inside the initial carbonate grains The not sintered CaO micrograins are the location of the carbonation reaction.A process of CO2 capture by calcium chemical looping was designed and built. It was made by two circulating fluidized beds, a carbonator where the CO2 capture were performed and the calcinator allowing the lime regeneration. These two circulating fluidized beds are coupled allowing a continuous CO2 capture.In spite of the low capture efficiency obtained on the scale of this pilot (from 18 to 23 %), these results seem encouraging for the development of this technology, considering the fact that many limiting factors of the capture efficiency disappear with the change of scale.

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